The Supreme Court ruled Tuesday that states can no longer be judged by voting discrimination that went on decades ago, in a decision that marks the end of a major civil-rights era reform.The 5-4 ruling rewrites a key tool of the Voting Rights Act of 1965, which for five decades has given the federal government unprecedented say in everything from how some states draw their congressional maps to where they place polling locations.

But the justices said after five decades, the law has had a dramatic effect in ending discrimination in voting, and said Congress must now come up with new ways of deciding who still needs federal oversight.Beneath the legal ruling is a broader social statement, with the justices saying that a state cannot be perpetually held responsible for past discrimination if there’s no evidence that it still exists.

“Congress —if it is to divide the states — must identify those jurisdictions to be singled out on a basis that makes sense in light of current conditions. It cannot rely simply on the past,” Chief Justice John G. Roberts Jr. wrote for the majority.